The present invention relates to the consolidation (cicatrization) between bone parts in which it is necessary to maintain the parts together for the duration of the process of union between them. Furthermore, the present invention also permits two parts of a bone to consolidate properly, correcting any tendency towards malformation thereof. More particularly, the present invention relates to a clip for osteosynthesis having elastic properties, and it also relates to the method and the instrument for the placing thereof.
Various elements are known which permit the cicatrization of two bone parts or fragments by holding them together and avoiding their movement insofar as possible. Thus, there are external elements such as casts and internal elements such as screws, plates, clips, etc. which perform the same function. Argentine Patent 203,977 refers to a curved nail for the treatment of fractures, it comprising an elongated body which at one end has a coupling part which is to be inserted into the bone. Types of plates and nails for the knitting of femur heads are known from Patent 212,889 and Patent 214,240. Connecting plates for two fragments of bones are also known from Argentine Patent 211,803 in which a plate with orifices for screws is placed over the parts to be connected.
Argentine Patent No. 236,884 refers to a fastening clip especially for osteosynthesis and, for its application, the clip must be inserted in the bone by at least one pair of legs while a bridge portion which connects the two legs together remains outside the bone and effects the connection between the two bone fragments. This clip is to be used especially together with a similar clip, each one placed on each adjacent portion of bone to be connected; the bridge portions of the two clips are then connected together by an elastic element which pulls the two bone parts together that are being united.
Although some of the known embodiments have given generally good results, the doctor is confronted with the problem that some connecting elements are bulky and complicated, which increases the traumatic suffering to which the patient is subjected and the smaller ones, like clips, once placed, do not succeed in efficiently fastening the bone portions together, it not being possible to avoid that one bone part turns with respect to the other or shifts. When it is desired to consolidate two bone fragments, it is necessary to have excellent contact between the parts as well as compression between bone ends. Scientific investigations have shown that by suitable compression between the parts to be connected, a faster consolidated of better quality is obtained.
Since, in order to place the parts to be connected in contact and fix them, it is necessary to work through the wound of the patient, it is preferred that the connecting means be as simple as possible. Therefore, those internal connecting elements which comprise plates and screws are not to be recommended, particularly in the case of simple fractures.
In order to avoid the foregoing, there are simple clips of U-shape which are very similar to those clips which are used in paper staplers. These U-shaped clips have their ends which are inserted in a bone portion sharpened and they maintain their position by the rigid structure of the legs of the U. However, these conventional clips maintain the same distance between the bone fragments and, therefore, if there is not coaptation, there is instability in rotation, which means that the bone portions-may turn with respect to each other and may even separate. This phenomenon would not occur if one succeeded in maintaining the bone ends compressed against each other.
For the contrary case, in which it is desired to maintain a force of separation between the bone fragments, which case is particularly useful for bone malformation connection, there are no clips which make it possible to obtain this spacing and, therefore, it would be very useful to have clips which make it possible to achieve this.
As stated above, this could be obtained by connecting elements such as plates and screws, but these are much bulkier and require major surgical procedures for the placing thereof.